Vaporizing type oil burner



y 1949- J.' w. MILLER ETAL 3 5 7 VAPORIZING TYPE OIL BURNER Filed lay 21, 1945 M INVENTOR. 2a JOHN w. MILLER Y WALDO 6. SMITH 27 FIG. 2 a 5W 7 ATTORNEY Patented May 17, 1949 UNITED STATES PATENT OFFICE VAPORIZING TYPE OIL BURNER John W. Miller and Waldo G. Smith, Lansing, Micln, assignors to Motor Wheel Corporation, Lansing, Mich., a corporation of Michigan Application May 21, 1945, Serial No. 594,986

10 Claims. 1

This invention relates to combustion apparatus for burning liquid fuel' and more particularly to burners of the vaporizing pot type.

The principal object of the invention is to provide a burner of the vaporizing pot type which burns cleanly, and without forming soot deposits at the lowermost stages of combustion without in any way interfering with the clean and efficient operation of the burner at the higher stages of combustion.

This object is attained by forming the bottom of the burner so as to confine the oil admitted to the burner at the lowermost stages of combustion to a relatively narrow zone adjacent the fuel inlet, and by providing bailles around this zone to eliminate, or at least minimize, eddy currents.

This object and others ancillary thereto will become apparent in the following specification when read in connection with the accompanying drawings, wherein:

Figure 1 is a more or less diagrammatic crosssectional view of a heater including a vaporizing pot type burner embodying the present invention;

Figure 2 is a fragmentary cross-sectional view of a burner embodying the invention; and

Figure 3 is a cross-sectional view taken on substantially the line 33 of Figure 2.

Referring now more in detail to the drawings, the invention is shown as being embodied in a vaporizing pot type burner I0 forming part of a radiant heater 9. The heater comprises a casing which is preferably a steel shell closed at the upper end and open at the lower end. The casing is mounted on a suitable base l2 which supports the casing above thefloor to permit air for combustion to enter the lower part of the casing. The burner I0 is mounted in the lower part of the casing as shown and the upper part of the casing forms a combustion chamber I! which is provided with a flue outlet II.

The burner 10 may be of the type disclosed in the patent to J. W. Miller et al., granted November 9, 1943, No. 2,334,117. The burner includes a tubular side wall and a bottom wall II. The side wall comprises an upper portion I5 and an upright flange "A which is preferably formed integral with the bottom wall H. The flange I M is welded to the lower extremity of the tubular side wall I5. The upper portion of the side wall I! is provided with a plurality of vertically spaced rows of substantially equidistantly spaced primary air inlet openings 20 to admit air to support combustion of the fuel.

Adjacent the top of the burner is a centrally apertured top wall Hi. The top wall rests upon an inwardly extending bead l9 formed in the side wall of the burner. A plurality of secondary air inlet openings 2| are formed in the side wall of the burner above the top wall l8. These openings 2i provide for the admission of secondary air to the burner.

Intermediate the upper and lower ends of the burner is a centrally apertured partition or baffle 22. A portion of the partition 22 is inclined downwardly. Its lowermost edge is located adjacent to and above the lowermost row of primary air inlet openings 20. r

A fuel inlet opening 23 is formed in the flange "A of the bottom I! directly below the lowermost portion of the partition 22. A threaded coupling 24 is welded to flange HA about the opening 23 to provide for attachment of a fuel conduit 25. The latter is connected to a suitable source of fuel. In the conduit 25 is a suitable metering valve 26 of conventional form by means of which the fuel supplied to the burner can be regulated.

A depression 21 is formed in the bottom wall ll of the burner immediately adjacent the perimeter thereof. The depression 21 is preferably of uniform width and extends slightly more than half way around the perimeter of the bottom of the burner, as shown in Figure 3. The depression is deepest at a point directly below the fuel inlet opening 23 and gradually shelves upwardly so that it runs out flush with the level of the main portion of the bottom wall at points a little more than half way around the burner.

Generally upright baiile means is located im mediately adjacent the inner periphery of the depression 21 and cooperates with the flange HA of the bottom It to provide an open topped enclosure 28 about the perimeter of the depression 21. The baflle means comprises a generally arcuate metal plate 30 having radial flanges 29 at the extremities thereof. The flanges 29 are somewhat closer to the fuel inlet 23 than the ends of I the depression 21 so that the latter runs out beneath the flanges 29 to permit oil to flow out of the depression onto the main part of the burner bottom. The flanges 29 are welded to the flange Located within the enclosure 28 are a plurality of upright auxiliary baflle members 32. The baille members 32 extend radially of the burner and their radially inner ends preferably are attached to the plate 30. Their radially outer ends may be attached to the side of the burner also, if desired. The upper extremities of the baffles 32 are flush with the top of the plate 30 and their lower extremities are approximately flush with the lower edge of the plate 30 and the upper edge of the depression 21.

Preferably the lower edge of the plate 30 is tight against the bottom wall of the burner. That arrangement is not to prevent the flow of fuel to the burner bottom wall outside of the depression, but to prevent air from entering the enclosure at 'the bottom thereof in substantial quantities.

When the burner isin operation and the fuel is turned down to what is usually termed pilot fire" only a small quantity of fuel is fed to the burner through the inlet 23. This fuel flows directly into the depression 21 and is confined thereto by the sides of the depression. Combustion then occurs principally within the enclosure 28. Air for combustion of the fuel within the enclosure enters the burner through the air inlet openings 20 and can reach the enclosure through the openings 3| in the plate 30. During the pilot fire stage of combustion, when the flame is confined principally to the enclosure and the zone immediately thereabove, the baffle means which is composed of the plate 30 and the auxiliary baffle members 32 obstruct those eddy currents which tend to flow in a generally circular direction around the burner bottom. The partition 22, which is located above the baille means 30 and 32, deflects those air currents which tend to flow down into the burner from the upper part thereof and prevent such air currents from disturbing the flame within the enclosure 28. By preventing these eddy currents, the low fire is improved very distinctly in cleanliness, eliminating any substantial deposit of soot on the cool parts of the burner and improving the efliciency of the burner as a whole.

When the fuel supply is turned down to its minimum flow the fuel may not fiow circumferentially of the burner within the depression 21 to any great extent and thus combustion may occur entirely within the section of .the enclosure 28 immediately adjacent the fuel inlet 23. However, when the fuel supply is increased slightly, the fuel may spread out within the depression 21 so that combustion occurs substan-. tially completely throughout the enclosure 28. At the higher stages of combustion fuel is admitted to the burner faster than it can be vaporized and burned within the enclosure formed by the baffle 30 and the side wall of the burner. The fuel then flows out between the lower edges of the flanges 29 and the bottom of the depression 21 onto the main part of the bottom wall l1. When that occurs the burner operates in its normal, manner just as though the baffle means 30 and 32 were not employed. In other words, at the intermediate combustion stages the portion of the burner below the partition 22 becomes a vaporizing premixing chamber with little or no combustion occurring therein and combustion taking place within the burner above the partition 22 and in the combustion chamber l3. At the high fire stage practically the entire burner becomes a vaporizing and premixing chamber and combustion occurs 4 at the top of the burner and in the combustion chamber I 3.

Thus, it will be seen that the present invention does not in any way affect the operation of the burner at intermediate and high fire stages, but it does improve to a marked degree the performance of the burner when it is operating at the extremely low stages of combustion. This improvement is due, as above pointed out, to the confinement of the fuel to a radially narrow zone about the perimeter of the burner bottom, and the elimination of eddy currents by means of the upright baffles 30 and 32 and at least a portion of the partition 22 located above the enclosure.

The scope of the invention is indicated in the appended claims.

We claim: a

l. A burner of the vaporizing pot type comprising a tubular side wall provided with a plurality of vertically and horizontally spaced apart air inlet openings therein, said side wall being round in horizontal cross-section, a bottom wall attached to said side wall, said bottom wall having a depression therein adjacent said side wall and concentric therewith adapted to receive liquid fuel, said depression extending along the perimeter of said burner bottom wall, generally upright baflle means located adjacent the inner perimeter of said depression and having upright ends engaging said side wall, said baffle means cooperating with said side wall to provide an open topped enclosure extending substantially entirelv around the perimeter of said depression, and auxiliary baffle means located within said enclosure and extending radially thereof between said side wall and said first named baffle means, said burner having a, fuel inlet adjacent said depression and having means connected to said fuel inlet for delivering liquid fuel to said depression.

2. A burner of the vaporizing pot type. comprising a tubular side wall provided with a plurality of vertically and horizontally spaced apart air inlet openings therein, a bottom wall attached to said side wall, said bottom wall having a depression therein adjacent the side wall and extending along the perimeter of the bottom wall and adapted to receive liquid fuel, said burner having a fuel inlet opening adapted to deliver fuel to said depression adjacent the center of the latter, a centrally apertured partition within the burner extending laterally across the same and located between the lowermost and uppermost air inlet openings in the burner side wall, generally upright baille means adjacent said bottom wall and having upright ends engaging said side wall, said baflle means cooperating with said side wall to provide an enclosure extending substantially entirely about the perimeter of said depression, the upper extremity of said bafile means being spaced a substantial distance below said partition.

3; A burner as defined in claim 2 wherein said side wall is round in horizontal cross-section and said depression is concentric with said side wall.

4. A burner as defined in claim 2 wherein said side wall is round in horizontal cross-section and said depression is substantially concentric with said side wall, the deepest portion of said depression being located adjacent said fuel inlet and the bottom of said depression being inclined up wardly from said deepest portion toward both ends of said depression.

5. A burner as defined in claim 2 wherein said side wall is round in horizontal cross-section and said depression is substantially concentric with said side wall, said baffle means being provided with circumferentially spaced air inlet openings therein located in spaced relation to the bottom wall of the burner.

6. A burner of the vaporizing pot type comprising a tubular side wall provided with a plurality of vertically and horizontally spaced apart air inlet openings therein, a bottom wall attached to said side wall, said bottom wall having a depression therein adjacent said side wall adapted to receive liquid fuel, said depression extending along the perimeter of said bottom wall, generally upright baflle means located adjacent the inner perimeter of said depression and having upright ends engaging said side wall, said baflle means cooperating with said side wall to provide an open topped enclosure extending substantially entirely around the perimeter of said depression, and auxiliary baiiie means located within said enclosure and extending radially thereof between said side wall and said first named bafiie means, said burner having a fuel inlet adjacent said depression and having means connected to said fuel inlet for delivering liquid fuel to said depression.

7. A burner as defined in claim 6 wherein the bafie means adjacent the inner perimeter of said depression is provided with horizontally spaced apart apertures spaced from the burner bottom wall.

8. A burner of the vaporizing pot type comprising a tubular side wall provided with a plurality of vertically and horizontally spaced apart air inlet openings therein, a bottom wall attached to said side wall, said bottom wall having a depression therein adjacent said side wall adapted to receive liquid fuel, said depression extending along'the perimeter of the burner bottom wall, generally upright bafiie means located adjacent the er perimeter of said depression and having upright ends engaging said side wall, said bane means cooperating with said side wall to provide an open topped enclosure extending substantially entirely around the perimeter of said depression, said burner having a fuel inlet adjacent said depression and having means connected to said fuel inlet for delivering liquid fuel to said depression, said depression being deepest adjacent said fuel inlet and the bottom thereof slopin upwardly away from said fuel inlet in both directions parallel to said side wall.

9. A burner as defined in claim 8 wherein said baiile means is provided with horizontally spaced apertures therein spaced from the burner bottom wall.

10. A burner as defined in claim 2 including auxiliary upright baflie means located within said enclosure and extending radially thereof between said side wall and said upright bailie means.

JOHN W. MILLER. WALDO G. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 623,012 Grimm Apr. 11, 1899 1,662,270 Jepson Mar. 11, 1928 2,091,658 Sturgis Aug. 31, 1937 2,162,844 Jenson June 20, 1939 2,186,156 Valjean Jan. 9, 1940 2,337,673 McCurtain Dec. 28, 1948 2,240,861 Sabins May 6, 1941 2,241,470 Miller May 13, 1941 2,293,697 Chadwick Aug. 25, 1942 FOREIGN PATENTS Number Country Date 814,024 France Mar. 8, 1937 

